A SIPOC diagram is often used in Lean and Six Sigma process improvement projects to:
- Define the stakeholders of a process (suppliers and customers)
- Define the scope and boundaries of the process
- Provide a high level overview of the process
- Understand how process outputs serve the end customer

It is typically used early in the project to gain alignment amongst the team and stakeholders.

How do you use it?

It is easiest to begin in the Outputs column. What does your process produce? It may be physical products, services, data/information, etc. List each output of the process in a cell in the Outputs column.

Next, move to the Customers column. Who consumes the outputs of your process? List each Customer in a cell in this column. A customer should be aligned with each of the outputs. Keep in mind that one Output may have many customers.

Complete the Inputs column next. What raw materials, data, etc must be fed into your process in order to get the outputs on the other side? List each input in a cell in the Inputs column.

Next, complete the Suppliers column. Who provides the inputs for the process? The suppliers can be individuals, companies, systems/databases, etc. Each input should be aligned with a supplier.

Finally, complete the Process column. Look at your Inputs column and determine what is the high level process to transform them into your Outputs. Note that the SIPOC diagram only includes a very high level view of the process. It should be summarized in 4-6 steps. A more detailed picture of the process can be created in a Process Flow Diagram. The process steps do not need to be aligned with the inputs and outputs.